Novel ultra-sonic boron refinement in distilled water for cost-efficient fabrication of MgB.sub.2./sub. bulk ceramic superconductors

0561608 - FZÚ 2023 RIV GB eng J - Článek v odborném periodiku
Arvapalli, S.S. - Miryala, M. - Sakai, N. - Murakami, M. - Jirsa, Miloš
Novel ultra-sonic boron refinement in distilled water for cost-efficient fabrication of MgB₂ bulk ceramic superconductors.
Ceramics International. Roč. 48, č. 19 (2022), s. 28102-28111. ISSN 0272-8842. E-ISSN 1873-3956
Grant ostatní: AV ČR(CZ) StrategieAV21/3
Program: StrategieAV
Institucionální podpora: RVO:68378271
Klíčová slova: bulk MgB₂ ceramics * boron ultra-sonication * distilled water medium * Jc enhancement
Obor OECD: Condensed matter physics (including formerly solid state physics, supercond.)
Impakt faktor: 5.2, rok: 2022
Způsob publikování: Open access

Cheap commercial boron was refined ultra-sonically in distilled water medium for various durations. X-ray diffraction pattern (XRD) indicated impurity-free nature of ultra-sonically refined boron. Field emission scanning electron microscope (FE-SEM) showed refinement of coarse boron to nanoscale. Rietveld phase fraction analysis on XRD pattern of sintered bulk prepared from ultra-sonically refined boron and Mg powder revealed a complete MgB2 phase formation, with a few impurities of MgO. FWHM (Full width at half maximum) is used to estimate crystallite size and microstrain. Tc,onset was around 38.5 K, with a sharp transition (ΔTc ∼ 0.5 K). Critical current density (Jc) of bulks prepared with B ultra-sonicated in distilled water for 15 and 30 min reached 295 and 305 kAcm−2 at 20 K/self-field, respectively. This is 35% increase in Jc showing the cost efficiency of this novel technique.
Trvalý link: https://hdl.handle.net/11104/0334182